1. Field of Invention
The present invention relates to a data processing system, an access control method, and an access control device for arbitrating competition when access requests from a plurality of processing means outputting data to a storage means compete.
2. Description of the Related Art
For example, there is a system where a plurality of processing apparatuses access a redundant array of inexpensive disks (RAID) or other storage device and transmit (broadcast) content data read out from the storage device at a predetermined output rate. The processing apparatuses for example access the storage device for various purposes other than the above transmission. Such a system employs a time slot system so as to reliably assign a fixed time during which access to the storage device is permitted at a predetermined period to each of a plurality of processing apparatuses or their ports. Due to this, each of the plurality of processing apparatuses or their ports accesses the storage device during time slots assigned to itself (see Japanese Patent Publication (A) No. 11-232205).
However, in a system employing the conventional time slot system explained above, since time slots are automatically assigned to the plurality of processing apparatuses or their ports even while not accessing the storage device and since access often ends without using all of the time slot period, there is the problem that access to the storage device is inefficient.